New Delhi– Maternal exposure to air pollution during pregnancy—particularly in the second and third trimesters—can lead to subtle but significant structural changes in the developing brains of unborn babies, according to new research published in The Lancet Planetary Health.
The study, led by the Barcelona Institute for Global Health (ISGlobal), found associations between prenatal exposure to pollutants such as nitrogen dioxide (NO₂), fine particulate matter (PM2.5), and black carbon, and alterations in fetal brain structures that are critical for motor coordination and overall brain development.
“During mid to late gestation, the fetal brain undergoes a key phase of development, making it especially vulnerable to environmental exposures like pollution,” said Dr. Payam Dadvand, lead researcher at ISGlobal.
Using advanced transvaginal neurosonography—a specialized ultrasound technique—the researchers analyzed data from 754 mother-fetus pairs collected between 2018 and 2021. This allowed them to assess subtle changes in fetal brain anatomy during the third trimester.
The study revealed that higher exposure to air pollutants was linked to increased volumes of the brain’s lateral ventricles, which are fluid-filled cavities located in each hemisphere, as well as enlargement of the cisterna magna, a cavity at the base of the brain. Both of these features are related to cerebrospinal fluid dynamics and brain structure integrity.
Researchers also observed a widening of the cerebellar vermis, a part of the brain essential for balance and motor coordination. These changes were also associated with delayed brain maturation.
“Clinically, we are now witnessing compelling evidence that even pregnancies appearing healthy by standard medical assessments may be impacted by environmental pollutants,” noted Drs. Elisa Llurba and Lola Gómez-Roig of the Hospital de Sant Pau and BCNatal-Hospital Sant Joan de Déu, respectively.
Although the observed changes were described as small at the individual level, researchers emphasized their significance from a broader public health perspective.
“These subtle differences matter when viewed across an entire population,” said ISGlobal researcher Laura Gómez-Herrera. “They reveal how deeply environmental exposures, like air pollution, can influence fetal brain development.”
The study calls for further research to validate these findings and urges the medical community and policymakers to raise awareness about the impact of pollution on prenatal health. (Source: IANS)
